LEASES - Components of Lease Expense and Payments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 5,763	$ 6,194	$ 11,744	$ 12,337
Short-term lease cost	625	645	1,303	1,154
Variable lease cost	1,383	642	2,045	1,446
Total operating lease cost	7,771	7,481	15,092	14,937
Finance lease cost:
Amortization of right-of-use asset	804	782	1,504	1,579
Variable costs	227	210	430	458
Interest costs	78	95	162	197
Total finance lease cost	1,109	$ 1,087	2,096	2,234
Payments for lease liabilities			9,700	10,800
Lease liabilities arising from ROU			12,300	5,100
Finance leases cost included in property, plant and equipment	31,600		31,600		$ 26,600
Accumulated amortization related to finance leases	14,900		14,900		13,500
Principal payments, finance lease liabilities			481	574
Investing cash flows for finance lease liabilities			3,400
Operating cash flows for finance lease liabilities			200	100
Finance lease, disposed				$ 1,000
Total	6,476		6,476		$ 5,459
Finance lease liability, current	$ 1,700		1,700
Repositioning of Wholesale Roaming Operations
Finance lease cost:
Right of use assets terminated			5,600
Lease liability terminated			5,900
Gain on lease termination			$ 300